The EXACTO (EXtreme ACcuracy Tasked Ordnance) rifle will conceivably be able to fire accurately at…
Read more Read more

We can't find a detailed explanation of just how that bullet swerves itself back on-target. DARPA's public description is, perhaps not surprisingly, rather vague:

The system combines a maneuverable bullet and a real-time guidance system to track and deliver the projectile to the target, allowing the bullet to change path during flight to compensate for any unexpected factors that may drive it off course. Technology development in Phase II included the design, integration and demonstration of aero-actuation controls, power sources, optical guidance systems, and sensors.

The technology, whatever it may be, promises to compensate for wind, dust, and other factors, increasing a sniper's accuracy and range and reducing the risk that a missed shot could give away the sniper's location. At one point in time, that would've sounded like comic book fantasy, but now that the first live fire has been successful, it's a stone-cold fact.